44 lines
1.0 KiB
Markdown
44 lines
1.0 KiB
Markdown
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# Functions
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Functions are first-class citizens in ginger. The simplest anonymous function
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can be created like so:
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```
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(. fn [x]
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(: + x 1))
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```
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This function takes in a single number and returns that number plus one. It
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could be assigned to a variable on the package using `def`, or by using the
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shortcut `defn`. The following two statements are equivalent:
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```
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(def incr
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(. fn [x]
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(: + x 1)))
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(. defn incr [x]
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(: + x 1))
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```
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## Variadic function
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Functions may take in any number of variables using the `...` syntax, similar to
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how go does variadic functions. The variadic variable must be the last in the
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function's argument list, and is used as a list inside of the function. A list
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may also be used as the input for a variadic function, also using the `...`
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syntax.
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The following is an example of both defining a variadic function and both ways
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of using it. `+` is a variadic function in this example:
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```
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(. defn avg [...x]
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(/
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(+ x...)
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(len x)))
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(: fmt.Println (avg 1 2 3 4 5))
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```
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